A system for preventing a rack fault condition of a passenger boarding bridge includes a plurality of electromagnetic sensors that are disposed for sensing separately a rotational movement of each one of a first and a second electromechanical screw jack, one electromechanical screw jack located adjacent to each lateral sidewall surface of the passenger boarding bridge. The system also includes a control circuit in communication with the plurality of electromagnetic sensors. The control circuit receives signals from the sensors, which signals are indicative of the sensed rotational movement of each one of the first and second electromechanical screw jacks. A value is determined relating to a rotational synchronization of the first and second electromechanical screw jacks. When the determined value is outside a predetermined range of threshold values, a control signal is provided for affecting the rotational movement of at least one of the first and second electromechanical screw jacks.

Provided is a plumbing device for plumbing and connection of a long member, at the time of installation vertically of the long member on an upper end of a lower member, which is used for plumbing the installed long member to connect with the lower member. The device includes a pair of splice plates to be attached onto both sides of a first and a second erection pieces and to be joined and fixed to the pieces, the first erection piece being arranged near the upper end of the lower member and the second erection piece near a lower end of the upper long member; a first wedge piece, to be inserted into a gap space made by the splice plates and the first and the second erection pieces, while slidably in contact with and supported by either the first or the second erection piece; a push-up piece, in the same gap space, to be located adjacent to the erection piece not in contact with nor supporting the first wedge piece, while supported by one of the splice plates so that vertical movement may be possible to be in contact with the adjacent erection piece; and a second wedge piece, for a fine adjustment, to be arranged between the first wedge piece to be inserted in the gap space and the push-up piece to be located in the same gap space, in a direction to cross the inserted first wedge piece, through the pair of the splice plates.

An interlocking wall and roof system for the protection of a building structure is disclosed. The interlocking roof and wall system is equipped with a plurality of supports that form downward facing open channels that are either already attached to the overhang of the roof or are easily attachable to the overhang. The system also includes a plurality of protective walls that surround the building structure. The protective walls can be lifted from a resting position to a position where at least a portion of the walls fit into the downward facing open channels of the overhang. These walls are lifted by a hydraulic lifting system. The invention also provides a complete building structure already fitted with the supports, hydraulic lifting system and protective walls.

A height adjustable jack piling assembly has a piling with a top and a bottom. A hinge axis is disposed on the top and a bearing plate is disposed at the bottom. A height adjustment mechanism extends upwardly from the bearing plate and through the piling to raise the piling, and the corresponding hinge axis, by operating the height adjustment mechanism from the top. The method includes placing a jack piling assembly and second lower piling, each having a hinge axis, into the earth and operating the height adjustment mechanism of the jack piling assembly to align the hinge axes.